Cord locks are often used on items such as ready-to-wear clothing, backpacks, bags, tents, and shoes and used for locking or adjusting cords. These cord locks can be roughly separated into two kinds. One kind is hard rubber cord locks, which are normally formed by two or more elements. For example, a kind of commonly seen cord lock is composed of three elements, including a pressing core, outer shell, and a spring. The spring is packed onto the pressing core, and then the packaged pressing core and springs are set into the outer shell. The locking and releasing of the cord lock is realized by pressing or releasing the inner core. This type of cord lock has a complex structure, multiple production steps, time intensive packaging, and high cost. Another type of cord lock only includes the two pressing core and outer shell elements. The pressing core is inserted into the outer shell, and the locking and releasing of the cord lock is realized by pressing or releasing the inner core. Although it is relatively simpler than the cord lock with three elements, it still is not superior in regard to the packaging process and cost. Other than the hard rubber cord lock, there is still another kind that is a soft rubber cord lock, and it can be made to only include one part. However, this kind of cord lock is limited by the insufficient durability of its own material. The force used to clamp the cord can be influenced by both [using the cord lock for] an extended period of time and the weather, easily resulting in a degraded ability to clamp the cord.